Let's start with quick lesson in panties. Panty styles are divided into a few basic shapes.
In terms of coverage a bikini panty falls between a thong and a brief panty, and covers the derriere (that's your backside), while sitting fairly low on your hips.

Classic bikini panties cover the back completely, and are lower in the front with the waist band resting between the hip and the navel.

A

sheer micro bikini
panty is designed along the same lines as low rise panties, and are ideal to wear with low-rise pants.

Some styles like g string bikinis are designed with g string sides, while other styles such as the sheer micro bikini have wider (more fabric) sides.